Add telemetry for loading/migrating mbconfig

Since we have multiple version for mbconfig, it will be helpful for us to add telemetry for loading mbconfig

Telemetries that worth tracking on top of my head are
- metadata for loading ( mbconfig version, model builder version, if need migration, if load succeed(*))
- metadata for migration (if migration succeed(**), and if not, if user click 'yes' on prompt window)

(*) loading mbconfig could fail if it's loading a newer schema, and we throw a prompt window to suggest user update model builder.
(**) migration fails only if it causes information loss

@beccamc for any other suggestions on telemetry